Recover energy from temperature

[rc4]

What causes the volume to move to the right.?

Me, but I move less to the right because vertical red surface move to the left in the same time. If vertical red walls don't move to the left in the same time I move to the right, I'm agree I give the same energy I recover. But Here, it's gas that move vertical red walls to the left, not me, the velocity of magenta walls is V but vertical red walls is V' with V' < V. The energy I gave is PSd, if d decrease (because V decrease for vertical red surfaces) I give less energy. For you the energy give to the system is the same if vertical red walls move to the left in the same time ?

[LibreEnergia]

Me, but I move less to the right because vertical red surface move to the left in the same time. If vertical red walls don't move to the left in the same time I move to the right, I'm agree I give the same energy I recover. But Here, it's gas that move vertical red walls to the left, not me, the velocity of magenta walls is V but vertical red walls is V' with V' < V. The energy I gave is PSd, if d decrease (because V decrease for vertical red surfaces) I give less energy. For you the energy give to the system is the same if vertical red walls move to the left in the same time ?

The gas doesn't...

1. 'Move itself' or
2. 'Compress itself'.
3. Neither do the walls containing the gas move without work input.

If it did these things then yes, your machine would work.

[rc4]

Could you explain, with formula, velocity, distance, etc. ? I prefer to understand with formulas. I Recover PdV, so I need to give PdV, but I give PSe' not PSe, and like e'<e because V'<V I give less energy. Don't forget, outside volume there is P, but inside volume there is 0.1P.

[PiCéd]

http://en.wikipedia.org/wiki/Enthalpy

[rc4]

If I use valves for red surfaces I can compute force on magenta walls. The mean of pressure is 0.45 bar so I need to give PSe but pressure is lower.  I don't recover energy from red valve, it's only for compress volume, so valve move "alone", imagine valve alone, independant.